This invention relates generally to wood bending machines and more particularly to a machine adapted to shape, form, bend set in a relatively short period of time solid or laminated wood strips into arcuate or curved forms for use, in custom crafted windows and doors, in wooden members for boats, pianos, furniture, and in other devices.
Machines or devices for shaping, forming, bending and setting solid, veneered or laminated strips of wood into arcuate or irregular shapes are known in the art.
Thus, for example machines or devices for shaping and setting frames or timbers used in the construction of boats and pianos are shown in U.S. Pat. No. 1,717,776; 229,198 and 333,615.
Other machines or devices are also known in the prior art which utilize a plurality of arcuately spaced clamping blocks either fixed or adjustably mounted on a table support to provide predetermined arcuate shapes for solid or veneered wood strips for doors and windows is shown in U.S. Pat. No. 927,975; 1,757,779 and 1,862,414.
Thus, in U.S. Pat. No. 927,975 the table support has a plurality of spaced parallel slots in which a corresponding plurality of clamping units are disposed, each clamping unit respectively mounted for manual movement in and along an associated parallel slot so that the respective clamping ends of the clamping units can be positioned and held relative the adjacent clamping unit to provide the desired arcuate shape for bending the elongated solid, veneered or laminated wood strip. Each of the clamping units have fixed or non-movable elements which are in alignment with respect to each other to provide the given arcuate shape, and coacting manually movable members, so that the board to be bent can be fixedly connected in the centrally located clamping unit and then bent from unit to unit serially and progressively away from the central unit and clamped by the movable clamping member progressively as the member is bent or set. In order to reset the apparatus, each of the clamping units must be moved along its respective associated parallel slot to whatever new position is required to provide a new predetermined arcuate shape.
In U.S. Pat. No. 1,757,779 the plurality of clamping units are fixed to the table top to permit the member to be bent to be clamped against a steel band which serves as the arcuate template for the desired arcuate design. The clamping units of the machine shown in this patent are fixed in position and can provide only a single arcuate shape.
Similarly, in U.S. Pat. No. 1,862,414 a plurality of clamping units are shown each of which has a fixed member. The fixed members on the respective clamping units are disposed in alignment with each other to form the desired arc to which the elongated solid veneered or laminated wood member is to be bent. Coacting with each of the fixed members is a clamping plate which is removably connectible as by suitable threaded means to the fixed member. The clamping plate acts to hold the elongated wooden member against the fixed member during the use of this machine. The clamping units can be adjustably positioned to establish a predetermined arcuate shape by means connecting the respective clamping units into a plurality of spaced apertures which are drilled into the table top to which the respective clamping units are connected.
Other patents show means for forming arcuate laminated trusses or beams for structural elements in building construction such as is shown in U.S. Pat. No. 2,399,348 and 3,835,904.
In U.S. Pat. No. 3,835,904 a mechanical device is shown for forming laminated beams by pressing freshly glued strips of wood against a rigid steel frame and holding them in assembled position until the beam is set and fixed into the disired shape.
In U.S. Pat. No. 2,399,348 a machine is shown for making laminated trusses or beams in which a plurality of parallel guideways provide means for pressing the laminated strips against a corresponding plurality of fixed vertically disposed studs which are positioned and shaped into the desired arcuate shape for the beams. The movable compression or pressing elements are reciprocably mounted and are arcuate towards and away from the aligned vertically disposed studs by a suitable type of hydraulic fluid operated pistons which move the presser elements in the parallel guideways.
Still other mechanisms for wood bending are various types of molding machines in which a female mold is pressed against a male mold or vice versa to provide the desired form or shape for the wood to be bent as is shown in U.S. Pat. No. 1,461,471; 2,335,480, and 3,027,923.
The present invention provides a still further improved machine for bending elongated, solid, veneer or laminated wood strips into a given semi-circular, oval, elliptical or an irregularly curved shape as may be desired.